There exist many known accelerator agents and systems for the curing and vulcanization of rubber(s) of either the natural or synthetic variety (and mixtures thereof) which are compounded for that purpose. These include various and numerous sulfur-containing materials, as are all set forth in the VANDERBILT Rubber Handbook, the Current Edition and which are knwon for such usage when employed individually or in combination with other materials.
Unfortunately, the great preponderance of satisfactory accelerator materials tend to be undesirably expensive. As is abundantly evident in the ensuing Specification, the accelerator ingredients employed in practice of the present invention are obtainable and providable by a relatively simple process utilizing generally readily available and relatively low cost starting raw materials.
The prior art in this particular area is of great magnitude. In fact, the basic fundamentals and operational principles and limitations of accelerators and curing agents for the vulcanization of rubber are so well known by those skilled in the art that further eludication thereof and elaboration thereon is unnecessary for understanding of the advance possibilated by and with the development of the present invention.
Although heretofore unknown as accelerator materials in and for rubber compositions, various amine form of esters, or amine-substituted esters, of phosphorodithioic acid, are recognized compositions of matter, as are disclosed in U.S. Pat. No. 2,586,656.